Hi guys. I've got a 2010 Duke 690 (usa spec) and I've put on heated grips, and taps and a controller for heated clothing too. I want to ride in comfort even when it's cold. Here's the thing... the Duke's charging system is rated at 224 watts. I'm worried that my electric gear is going to over load it.

When you look at the specs of a KTM with a 990, like the SM-T, it has a charging system with 450 watts. Kinda like my BMWs or my Gold Wing. Big output with plenty of room for accessories. Today I was at a friends house and we put an inductive amp meter around the ground strap to the battery. Not sure what unit of measurement we were actually looking at because the meter was set up for AC, but at idle, the number was 1.1 so it was reading something. When revving the engine, the number went up to about 8. When revving with the heated grips on, it went to 5. When revving with the heated grips and the heated vest plugged in and cranked up to high, it stuck at 1.2 even at higher RPM. With heated grips and the high beam headlight on, it stuck at 1.2 also. Not a whole lot of headroom I guess. It never went below 1.

What can I do to upgrade the charging system? Does anyone make a stator with more output? Would a stator with a higher rating from another KTM plug in in place of the Duke's? If I can't go that route, I'm thinking I can spare some wattage at least by replacing the headlight with a lower wattage HID kit??

The Duke has the same stator as all other 690s - Enduro (R), SMC, Supermoto, Rally Replica. Unfortunately there is no higher power version available that will fit, neither OEM nor aftermarket.

Work on reducing inefficiencies, like going to better all LED and/or HID lighting (obviously blinkers with a proper relay), replacing the stock regulator with a MOSFET one (Uller and RoninMoto have done a write up), using dual element heated grips instead of resistors, etc.

I went looking for the write ups you mentioned, but couldn't find them. I tried searching for MOSFET and also by user name... Any links to those write ups? I'd like to read them.

The grips I put on were the KTM hard parts version with 4 settings (though they're all pretty hot). I had to trim the throttle grip a bit, and when I did I noticed that I could see a fine metallic mesh between the layers of rubber. I'm hoping they're efficient.

Also, using a DC capable inductive amp meter I measured:

With the clamp around the positive wire at the battery, at idle, no accessories running, current flowing through is hovering around 1 amp (12w).

With heated gear going full blast, it's around 8 amps (96w). Put the high beam on and it goes up to 13 or so (156w). Anything off idle and these numbers go up.

So if we're talking 12V, the 224w charging system puts out 18+ amps.

When I look at charging voltage, with grips and all gear on the charging voltage at the battery does not go much higher than 12.8 at idle, and into the 13's at 4000 RPM. With less gear on, that number rises. I did sap the battery a bit when I was trying to see what just the gear and headlight draw with the bike not running. With everything on full hot and even the high beam on, but engine off, it spiked a draw of about 16 amps off the battery. So if the engine running at idle with no gear on is 1 amp, and everything else is 16, then I have an amp left, or 12w of charging, at idle. Makes me miss my BMWs...

I think to be safe and know I'm always going to have a charged battery, I should not use everything at once like I did during the test. I don't think I'd want everything on at full hot anyway... it'd be too hot. I probably won't be riding too often at night in the cold with the high beam on either. And I think the heated gloves draw less than the heated grips, probably have to run them at less power to get the same effect.

I just don't want to cook any important charging system components. So, if I could learn more about that MOSFET upgrade, that'd be helpful.

I contacted Ricksmotorsportelectrics.com and while they don't have an uprated stator, they say if I use their hot-shot plug and play Mosfet rectifier/regulater, I'll get an additional 40 watts of power. Click Here to see it.

The other thing I've been wondering... I wonder if someone who sells parts has a stock 690 stator and a stock 990 stator on hand to eyeball them side by side and see if they're the same size. I took a look at the parts fiche but that's just a drawing. They've got the same plug on them. If they were interchangeable that'd be awesome, wouldn't it?

Thanks Lukas. I'm waiting on UPS to deliver a voltage gauge I'm gonna mount to keep an eye on charging system status. If it's showing that I'm running low on available voltage/current I'll look into the mosfet setup you recommended. Thanks!

I've found Ricks to be a trusted authority on electronics here in the USA. Maybe you misunderstood their claim or you could ask for a clarification. I just used his RR on my 950, I'm impressed with it as I've been with his other parts for my older KTMs. He solved my "Electroshort" RFS issues after the company failed to make it work in 4-5 attempts.

Here is an email I got from them after inquiring about the uprated stator, or rewinding a stock one to get more watts. Copied and pasted:

Hi Eric,

Our rec/reg (part# 10-013H) will give you an additional 40 watts of electrical power. If that's enough, it would be a super easy upgrade for you! We have them in stock & retail price is $150 + free ground shipping. Just click on the link below to see a photo and/or place your order.

Your best bet is to add loads slowly and monitor charging voltage. Get a small voltmeter so that you can monitor voltage while you ride. Make sure that the charging system will supply at least 13V as you ride. You'll probably have to turn your heating gear off at stops to keep from discharging the battery. (Charging output is lowest at idle.) If your bike has incandescent tail lights and brake lights, that's a good place to save power with much more efficient LEDs.